This invention relates to a turnstile allowing an emergency exit. In particular it relates to a turnstile of the type sometimes termed as a “speedgate”.
In such products panels or other mechanical barriers or obstructions are mounted on either side of a channel or lane through which persons have to pass and are mechanically moved, typically pivoting about a vertical axis, to allow persons to pass through a channel from one area to another. They thus perform the function of a turnstile. Often this is facilitated by the presentation of a credential or token such as a smartcard, finger print or similar which must be presented to a suitable reader and which, once the user's credentials have been authorised, either causes the/or each panel to open or releases a break/lock which enables the user to physically push the barriers to pass through. They may allow movement in either direction (ie for entry or exit (egress)) and passage in both or just one of the directions may require credential or token authorised entry. Sometimes the operation in either direction may be triggered by a mechanical switch or other means.
Such products therefore provide a security function to disallow unauthorised persons from entering a secure area for example.
Sometimes there is no need for the use of a credential on exit. Instead, a sensor or sensors detect the presence of a person wishing to exist and the barrier opens automatically and subsequently recloses. In some simple turnstile type systems free exit is provided by means of a directional brake which enables a user freely to pass through in the exit direction but not to pass through in the entry direction unless authorised.
In a situation where authorisation is normally required for exit there is sometimes a requirement that in an emergency egress situation it must be possible to simply push the panel away (ie in the direction allowing movement in the exit direction) in order to escape an area quickly. It is possible also to employ directional brakes, clutches and so on. However, a disadvantage of this is that if a directional brake or clutch is provided it may be possible for an unauthorised user wishing to enter to simply pull a panel or door in the exit direction and thereby facilitate unauthorised entry.
It is also possible to provide a ‘crash bar’ (crash) type switch (such as the “push for exit” bars seen on emergency exit doors) such that an exiting person could operate it to facilitate exit without use of a token in an emergency situation. One problem with this is that such a crash bar switch or switches need to be apparent and easily operated and there is the possibility that they may be operated by an unauthorised person from the insecure side of the passageway.
In addition, in many situations it is of course paramount that people exit as soon as possible, yet it is also important that people's movements be monitored, and that the identity and the number of people left in a space is known, so there is a need for an “emergency” exit system, or mode, which still encourages users to present credentials if possible.
The present invention therefore arose in an attempt to provide an improved system allowing free emergency exit yet still preventing unauthorised users from entering using that system.